Two-step switch



June 24, 1930. COLBY 1,765,567

TWO-STEP SWITCH Filed Aug. 50, 1923 I WIT ES SES: HNVENTOR BY M ATTORNEY 1 Patented June 24, 1930 UNITED STATES PATENT OFFICE I can A. COLBY, or IRWIN, rnunsrnvanm, ASSIGNOB. TO wnsrmenoosn ELECTRIC a MANUFACTURING COMPANY, A conronarron on rnnnsnvnma TWO-STEP SWITCH Application filed August 30, 1923. Serial No. 860,125.

My invention relates to switches and more particularly to those used in connection with 1 household appliances.

One object of my invention is to provide a switch which may be set in one position and subsequently moved through a series of positions.

Another object of my invention is to provide a switch which is set at one position and m which is biased to another position through a plurality of intermediate positions.

Another object of my invention is to pro vide a switch which is particularly useful in connection with electrical appliances wherein it is desired to employ a switch to perform a plurality of operations automatically in a desired sequence. In the operation of electrical appliances particularly electrical ranges,it is often found an desirable to set the main controlling switch in such position that a circuit ma be closed at a desired time and the circuit t rough the electrical appliance will continue for a certain period of time, or until the thermal condition of the electrical appliance becomes such as to make it advisable to interrupt the current being supplied thereto. In connection with electrical ranges, this advantage is particularly pronounced when a clock is set to energize the oven at a given time and the current through the oven is interrlipted when the oven has reached a given temperature, all these operations being entirely automatic after the setting of the clock and the control switch.

My invention relates to the switch and its details of construction for accomplishing the foregoing objects.

In the accompanying drawings Figure 1 is a diagrammatic view of apparatus-and circuits embodying my invention. Fig. 2 is a face view of a switch embodying my invention- In the preferred embodiment of my invention, an electrical household appliance 1, such as an electric range, having a heating element, is supplied with electrical energ from asupply circuit 2 comprising the con uctors 3 and 4, the connection between the circuit 2 and the device 1 being controlled by a switch 5. In addition to the switch 5, a thermostatic switch 6 and a clock (not shown) provided with a pair of relatively movable contact members 7 are associated with the electrical heating appliance 1.

The switch 5 comprises a tact member 8 in electrical the heating appliance 1, and a movable constationary conconnection with tact member 9, which is connected to the con- A pair of latches l7 and 18 are provided "for engaging the extension 12. The latches 17 and .18 are controlled by electromagnets 19 and 21,-respectively. The coil of the electromagnet 21 is in circuit with the contact members 7 of the time clock, while the coil of the electromagnet 19 is in circuit with the thermostatic switch 6.

As is shown in Fig. 2, the face of the switch is provided with a plurality of indicia which correspond to the several positions of the movable contact member 9, one of which being termed the set position, another the on position and the third the off position. A rotatable handle 22 provided w1th an indicator 23 is attached to the pivotal support 13 to move the contact member 9 in a counter clockwise direction and thereby wind the spring 14.

In order to operate an electrical heating appliance 1, equipped with my improved switching mechanism, the operator sets the indicator 23 on the switch 5 to the set position, which operation places the contact member 9 in position against the stop 15 and places the extension 12 beneath the latch 18 where it isheld against the bias of the spring 14. At the same time, the operator sets the clock mechanism. for the time at which the relatively movable contact member 7 shall close.

At the proper time, the clock moves the switch-operatin mechanism therefor comrelatively movable contact members into conprising a plura ity of independent electrotact to complete the circuit from the conducresponsive latches, a spring for biasing one tor 4 through the coil of the electromagnet of said contact members in one direction, 21 to the conductor The energization of clock-controlled contact members, and a. the electromagnet 21 causes the latch 18 to thermo-responsive member, said clock-con- 70 be withdrawn from the extension 12. The trolled contact members controlling one of latter, together with the contact member 9, said latches for causing said spring to move is then turned in a clockwise direction by the one of said contact members so as to engage m spring 14 until the contact members 8 and 9 the other of said contact members and said are in their closed position and the extension thermo-responsive element controlling an- 12 engages the latch 17. The electrical heatother of said latches for causing said spring ing appliance 1 is then supplied with a curto disengage said contact members in acrent by a circuit which extends from the concordance with a predetermined thermal conductor 4 through the conductor 11, contact dition of said thermo-responsiveelement.

members 8 and 9, and heating appliance 1 to 2. Switch mechanism comprising a stathe conductor 3. During this operation, the tlonary member, {movable COIItaCt indicator 23 moves to the position indicated member, a spr g n rmally biasing said movby th d on th f f th it h able contact member in one direction, and a go This circuit persists until the electrical latchlng mechanlfim mp p l y heating appliance 1 reaches a predetermined of electForesponslve c011? d a l n temperature, whereupon the thermostatic mechanlsm of Sald c0115 E P element of the switch 6 expands and closes mechamsm, and]! P g f f the circuit extending from the conductor 4 for another of 551d @0115 p through the thermostatic member 6, and the thermoresponslve by Said electromagnet 19 to the conductor Upon movable contact member is successively rethe energization of the electromagnet 19 the leasedlatch 17 is drawn away from the extension In l y f, I have hereunto 12, whereupon the spring 14 moves the con- Subscribed my name t'hls 23rd y of 80 tact member 9 out of engagement with the gustv 1923- 95 stationary contact member 8 and into the ORA COLBY- off position where the contact member 9 rests against the stop member 16. At the same time, the indicator 23 on the switch :5 face moves to the off position. 100

As soon as the temperature of the electrical heating appliance 1 falls to a predetermined value, the thermostatic switch 6 interriipts the circuit through the electromagm net 19, whereupon the entire circuit is deenergized. In order to restore the circuit to the position shown in Fig. 1, it is only necessary to turn the knob 22 so-that the indicator 23 points to the set position, after which the foregoing cycle of operations may no be repeated upon the closing of the clockcontrolled contact members 7.

It will thus be seen that I have provided a simple and effective switch for the operation of electrical heating appliances, particuus larly electrical ranges, which switch may be set in one position and which will thereafter automatically complete a desired cycle of I operations. Although I have described a specific emno bodiment of my invention, it will be obvious to those skilled in the art that various modifications may be made in the structural parts thereof without departing from the prino ciples set forth. I desire, therefore, to be 125 limited only to the spirit and scope of the appended claims.

I claim as my invention: 1. Switch mechanism comprising a pair of 66 relatively movable contact members, a 130 

